1. Field of the Invention
The present invention relates to the field of design and construction of shoes. More particularly, the present invention relates to the field of design and construction of interchangeable heels for shoes.
2. Description of the Prior Art
The heels of shoes, particularly the high heels of women's shoes, are extremely fragile and can be damaged easily. When the heel is damaged, it is often very expensive to have it repaired. In addition, it is strenuous to walk long distances in high heels. Many businesswomen prefer to have low-heeled shoes for walking and then wear the high heel shoes during work. At present, this requires the women to have two sets of shoes; a pair of low heel shoes for walking and a pair of high heel shoes for wear during work. Making the heels interchangeable is one way to solve this problem.
The following eleven (11) prior art patents were uncovered in the pertinent field of the present invention which relates to the design and construction of interchangeable heels.
1. U.S. Pat. No. 2,795,866 issued to Perugia on Jun. 18, 1957 for "Ladies' Shoes" (hereafter "the Perugia Patent").
2. U.S. Pat. No. 3,064,367 issued to Henatsch on Nov. 20, 1962 for "Replacement Heel Structure" (hereafter "the Henatsch Patent").
3. U.S. Pat. No. 3,077,680 issued to Moustakidis el al. on Feb. 19, 1963 for "Removable Shoe Heel" (hereafter "the Moustakidis Patent").
4. U.S. Pat. No. 3,432,945 issued to Cesta on Mar. 18, 1969 for "Replaceable Heels For Shoes" (hereafter "the Cesta Patent").
5. U.S. Pat. No. 3,754,340 issued to Pais on Aug. 28, 1973 for "Devices For Attaching Heels To Shoe Soles" (hereafter "the Pais Patent").
6. U.S. Pat. No. 4,214,384 issued to Gonzalez on Jul. 29, 1980 for "Replaceable Heel Construction For Shoes" (hereafter "the Gonzalez Patent").
7. U.S. Pat. No. 4,363,177 issued to Boros on Dec. 14, 1982 for "Style Convertible Footwear" (hereafter "the Boros Patent").
8. U.S. Pat. No. 4,670,996 issued to Dill on Jun. 9, 1987 for "Women's Shoes With Flexible Spring Steel Shanks For Use With Replaceable Heels Of Different Height" (hereafter "the Dill Patent").
9. U.S. Pat. No. 5,058,290 issued to Koehl et al. on Oct. 22, 1991 for "Shoe Construction With Self Seating Removable Heel"(hereafter "the Koehl Patent").
10. U.S. Pat. No. 5,079,857 issued to Clifton on Jan. 14, 1992 for "Shoe Having A Detachable Heel" (hereafter "the Clifton Patent").
11. U.S. Pat. No. 5,133,138 issued to Durcho on Jul. 28, 1992 for "Replaceable High Heel" (hereafter "the Durcho Patent").
The Perugia Patent discloses a ladies' shoe having a replaceable heel. The heel is provided with a metal tenon curved along a circular arc in the direction of its length. The insole of the shoe is a mortise slide which is curved with the same radius of curvature as the tenon and the inside section of which corresponds to that of the tenon. To mount the heel to the shoe, the tenon engages in the mortise slide and is pushed until the heel comes against the extreme edge of the sole. To disengage the heel from the shoe, the heel is pulled towards the outside. The Perugia Patent also teaches an assortment of heels of different shapes, styles and colors.
The Henatsch Patent discloses a replaceable heel structure. The heel consists of two portions. The first portion is a tread-retaining portion which is attached to the bottom of the sole, and the second portion is the tread portion which is slidably attached to the tread-retaining portion. The Henatsch Patent is designed with a flat heel.
The Moustakidis Patent discloses a removable shoe heel. The heel assembly is permanently attached to the base plate of the shoe.
The Cesta Patent discloses a replaceable heel construction for shoes. The heel base carries a latch plate with rear and front openings having marginal tongues, the rear tongues being inclined and providing fulcrums and guides and the front tongues being upright and providing guides.
The Pais Patent discloses an apparatus for coupling a shoe heel to a shoe. It includes an elongated plate used as a shank which extends up to and adjacent the sole back end.
The Gonzalez Patent discloses a replaceable heel construction for shoes. A coupling element is positioned to receive wings of another coupling element. Upon full insertion of the wings in the slot of the coupling element, flanges will underlay the wings, the slot conforms to the configuration of the wings, and a resilient locking tab will snap-down into a locking groove.
The Boros Patent discloses convertible footwear. A detachably attachable heel is secured adjacent the heel portion of the sole by lock means which include a threaded stud for threadedly engaging a cavity within the sole.
The Dill Patent discloses a woman's shoe with flexible shank for use with replaceable heels of different sizes. It includes an elongated flexible spring steel shank which is nestled within a slot between the insole and sole and anchored at one end. A high heel registers with the heel portion and interlocking fasteners. Upon limited rotation of the heel relative to the shoe, it removably anchors the heel upon the shoe. The heel upon limited angular rotation and disengagement of the fasteners is adapted for removal and replacement by a low heel having similar fasteners. The shank moves within the slot to compensate for the change in height. The interlocking fasteners include opposed interconnected lock segments and anchor flanges secured to the heel and heel portion respectively. An alignment pin in the heel projects into an alignment opening in the sole preventing relative rotation of the heel and heel portion to prevent disengagement of the segments and flanges.
The Koehl Patent discloses a shoe construction with a self-seating removable heel. A high heel is removably attached to the shoe and has an enlarged upper end portion with an inclined upper surface carrying a dove-tail locking member that extends upwardly from the high heel upper end portion inclined surface. The locking member includes a pedestal with a dove-tail sidewall that corresponds to and registers with the socket so that the heel can be attached to the socket by moving the heel pedestal into the socket in a fore to aft direction. The pedestal and socket are thus loaded during normal use of the shoe, so that during walking, the heel pedestal is continuously forced rearwardly into the socket.
The Clifton Patent discloses a shoe having a detachable heel. The shoe includes a foot receptacle portion having a threaded stem extending downwardly from a heel plate fixedly attached to the bottom of the foot receptacle portion which selectively receives a shoe heel in threaded engagement. A spring-biased locking pin is disposed in the shoe heel which engages a locking pin slot formed in the heel plate of the foot receptacle portion.
The Durcho Patent discloses a replaceable high heel. The device is an improved shoe which includes a shoe having an upper, a sole, a block extending downwardly from the lower portion of the sole adjacent to the heel, and a magnetic plate facing downwardly from the block. An improved replaceable heel includes an upper surface with an upwardly facing recess and a magnetically responsive plate which faces upwardly on the lower surface of the recess.
One of the problems of the prior art interchangeable heels is that they often have very complicated structures. This often increases the manufacturing costs and therefore the price of the shoes. Another problem of the prior art interchangeable heels is that they are often hard to handle, some even requiring a tool to detach the heel. A further problem of the prior art interchangeable heels is that they are not durable. In most prior art design and construction, the mating members between the outsole and the heel are part of the structure of the heel or the outsole of the shoe. Therefore, the strength and durability of the mating members are limited by the properties of the materials used for the construction of the heel or the outsole of the shoe.
It is desirable to design and construct shoes with interchangeable heels which are easy to handle, durable and inexpensive to manufacture.